Femoral nail with enhanced bone conforming geometry

ABSTRACT

A femoral nail includes a proximal section, a distal section remote from the proximal section, and an intermediate section disposed between the proximal section and distal section and having first and second curved portions. The first curved portion is positioned closer to the proximal section than the second curved portion. The second curved portion is curved in a first plane, and the first curved portion is curved in the first plane and a second and third plane.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing date of U.S.Provisional Patent Application No. 62/657,279, filed on Apr. 13, 2018,the disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

The skeletal system includes several long bones including the femur. Thefemur is the longest of the long bones and is generally divided intothree regions: the proximal femur, distal femur, and femoral shaft.Femoral fractures, which are commonly caused by acute trauma, can occurat or between any one of these regions. Such fractures often requireinternal devices to reduce and immobilize the fractured bone.

One such device is a femoral, intramedullary nail. Femoral nails areelongate structures that are inserted into an intramedullary canalthrough either the proximal femur or distal femur. Such nails aretypically bent along their respective lengths in an attempt to followthe natural curvature of a human long bone, such as the anterior bowfound in virtually all human femurs.

However, since anatomy varies from patient to patient, it has beendifficult to develop appropriate femoral nail geometries that aresuitable for the entire patient population. This difficulty has beenconfirmed by recent database analyses of femurs that have found thatcertain curvatures of the human femur are greater than originallyconsidered. In this regard, current femoral nails are generallydisproportionately curved relative to the femurs into which they areimplanted. This disproportionality may result in impingement of thefemoral cortex during implantation potentially resulting in fracture andalso malalignment of the femoral nail which can be uncomfortable for thepatient and result in less than desirable outcomes. Therefore, furtherimprovements are desirable.

BRIEF SUMMARY OF THE INVENTION

A femoral nail is disclosed that includes a proximal section, a distalsection, and an intermediate section. The proximal and distal sectionsextend along their own axes and are substantially straight. Theintermediate section is disposed between the proximal section and distalsection and includes a first curved portion, a straight portion, and asecond curved portion. The straight portion is disposed between thefirst and second curved portions. The second curved portion is curved ina first plane and has a radius that substantially matches a radius of ananterior bow of a patient's femur as may be approximated based upon adatabase population analysis. The first curved portion is curved in thefirst plane and also in a second and third plane. The second planeintersects the first plane at an oblique angle, and the third plane is aresultant of this oblique angle and the magnitude of the bends of thenail in the first and second planes. Such multiplane curvature has beendetermined by database analysis to provide optimal fit for the generalpatient population and to reduce incidence of femoral corteximpingement.

In one aspect of the present disclosure, a femoral nail includes aproximal portion configured to engage a driving tool for driving thefemoral nail into a femur, a distal portion remote from the proximalportion, and an intermediate portion disposed between the proximal endand distal end. The intermediate portion includes a plurality of bendssuch that a first bend is in a first plane, a second bend is in a secondplane, and a third bend is in a third plane. The first and second planesintersect at an oblique angle relative to each other. The third bend isa resultant of the first and second bends and has a magnitude greaterthan the first and second bends.

Additionally, the distal end may be straight and may include a pluralityof through-holes extending through the distal end in a directiontransverse to a distal end axis. The first plane may be greater than 80degrees and smaller than 120 degrees relative to the second plane. Inone example, the first plane is preferably 100 degrees relative to thesecond plane. The first plane may extend in an anterior-posteriordirection, and the second plane may extend substantially in amedial-lateral direction.

Continuing with this aspect, the first bend may be 3 degrees, the secondbend may be 4 degrees, and the third bend may be greater than 4 degrees.The intermediate portion may have a radius of curvature in the firstplane. Also, the proximal end of the femoral nail may include aplurality of through-holes extending therethrough. At least a first andsecond through-hole of the plurality of through-holes may haverespective first and second through-hole axes that lay in the secondplane. Furthermore, the proximal end may include at least one rotationalalignment characteristic for indicating a rotational alignment of thefemoral nail relative to a femur. The rotational alignmentcharacteristic may be rotationally offset from the third plane by anacute angle. The acute angle may be less than 50 degrees. The rotationalalignment characteristic may be an engagement notch configured to engagethe driving tool. Also, the third plane may intersect the second planeat an acute angle less than 50 degrees. Each of the bends may be anequal distance from a terminal end of the proximal portion.

In another aspect of the present disclosure, a femoral nail includes aproximal section that has a longitudinal axis extending along itslength, a distal section remote from the proximal section, and anintermediate section disposed between the proximal section and distalsection. The intermediate section has a straight portion and first bentportion. The first bent portion is disposed between the straight portionand the proximal section. The first bent portion is bent in first,second, and third planes such that a longitudinal axis of the straightportion is oriented relative to a longitudinal axis of the proximalsection by first, second, and third angles within the respective first,second, and third planes, and wherein the first, second, and thirdangles differ from one another.

Additionally, the intermediate section may also include a second bentportion disposed between the straight portion and distal section. Thesecond bent portion may be bent in the first plane. The second bentportion may have a radius of curvature of 500-1500 mm. The proximal anddistal sections may be straight along their respective lengths. Themagnitude of the third angle may be a resultant of the respectivemagnitudes of the first and second angles and the orientation of thefirst and second planes relative to each other. The first angle may be 3degrees, the second angle may be 4 degrees, and the third angle may bemore than 4 degrees. The first plane may be greater than 80 degrees andsmaller than 120 degrees relative to the second plane. The proximalsection may include a first screw hole configured to direct a bone screwtoward a femoral head when implanted within a femur. The bone screw holemay define a screw hole axis lying in the second plane. The distalsection may include a second screw hole extending therethrough anddefining screw hole axis lying in the second plane.

In a further aspect of the present disclosure, a femoral nail includes aproximal section, a distal section remote from the proximal section, andan intermediate section disposed between the proximal section and distalsection. The intermediate section includes first and second curvedportions. The first curved portion is positioned closer to the proximalsection than the second curved portion. The second curved portion iscurved in a first plane, and the first curved portion is curved in thefirst plane and a second and third plane.

Additionally, the second curved portion may be curved in the first planeand only in the first plane. The distal section may extend from thesecond curved portion and terminate at a distal tip. Also, the first andsecond planes may be oriented relative to each other at an obtuse angle,and the third plane may be disposed between the first and second planesand may be oriented relative to the first plane at an acute angle.

In an even further aspect of the present disclosure, a femoral nailincludes a first section having a first screw hole extending through asidewall thereof and defining a screw hole axis configured to extendtoward a femoral head when the femoral nail is implanted within a femur.The screw hole axis lies in a first plane, and a second section extendsfrom the first section and has first and second curved portions. Thefirst curved portion is positioned closer to the first section than thesecond curved portion. The first curved portion is curved in the firstplane and a second and third plane. The first curved portion has aproximal-distal length greater than that of the first curved portion.

Additionally, the second curved portion may terminate at a distal tip ofthe femoral nail. The nail may also include a distal section extendingfrom the second curved portion. The second curved portion may be curvedin the second plane. The first and second planes may be orientedrelative to each other at an obtuse angle, and the third plane may bedisposed between the first and second planes and may be orientedrelative to the second plane at an acute angle.

BRIEF DESCRIPTION OF THE DRAWINGS

The features, aspects, and advantages of the present invention willbecome better understood with regard to the following description,appended claims, and accompanying drawings in which:

FIG. 1 is a schematic representation of a prior art femoral nailimplanted in a proximal end of a femur.

FIG. 2 is a side view of a femoral nail in a plane extending in adirection A.

FIG. 3 is a partial cutaway side view of the femoral nail of FIG. 2rotated 180 degrees.

FIG. 4 is a front view of the femoral nail of FIG. 2 in a planeextending in a direction B.

FIG. 5 is a rear view of the femoral nail of FIG. 2 in a plane extendingin a direction C.

FIG. 6 is a top view of the femoral nail of FIG. 2.

FIG. 7 is another top view of the femoral nail of FIG. 2.

FIG. 8 is a schematic representation of the femoral nail of FIG. 2 in aCartesian coordinate system.

FIG. 9 is a schematic representation of the femoral nail of FIG. 2overlaying the prior art femoral nail and femur of FIG. 1.

FIG. 10 is a lateral view of a left leg femur.

DETAILED DESCRIPTION

When referring to specific directions in the following discussion ofcertain implantable devices, it should be understood that suchdirections are described with regard to the implantable device'sorientation and position during exemplary application to the human body.Thus, as used herein, the term “proximal” means close to the heart andthe term “distal” means more distant from the heart. The term “inferior”means toward the feet and the term “superior” means toward the head. Theterm “anterior” means toward the front of the body or the face and theterm “posterior” means toward the back of the body. The term “medial”means toward the midline of the body and the term “lateral” means awayfrom the midline of the body. Also, as used herein, the terms “about,”“generally” and “substantially” are intended to mean that slightdeviations from absolute are included within the scope of the term somodified.

FIG. 10 depicts an exemplary left leg femur. The femur has a proximalfemur 120, distal femur 121, and femoral shaft 122 that extends betweenthe proximal and distal femurs 120, 121. Proximal femur 120 includes agreater trochanter 124 and femoral head 126. As can be seen in FIG. 10,femoral shaft 122 has an anterior bow such that the femur curvesanteriorly in an anteroposterior extending plane. However, suchcurvature does not extend into proximal femur 120 which results in aslight posterior curvature or transitional bend 128 where femoral shaft122 and proximal femur join 120.

FIG. 1 depicts an exemplary prior art femoral nail 100 implanted withina femur, such as the femur in FIG. 10, in an antegrade manner. As shown,the construction of femoral nail 100 is such that it has a portion 110that impinges on the anterior cortex of the femur at transitional bend128 between femoral shaft 122 and proximal femur 120. Such impingementmay be caused by an underestimation of the curvature of the femur and,as illustrated in FIG. 1, may occur at transitional bend 128 which is alocation at or near the transition or necking down of the proximal femur120 to the femoral shaft 122. This can result in fracturing of the boneparticularly as the nail 100 is impacted into the intramedullary canalof the femur. Moreover, even if fracture does not occur, the nail 100may press against the cortex of the bone which can result inmalalignment of both fracture fragments as well as the femoral nail 100within the intramedullary canal as the nail may be constrained fromcoming to the desired seated position. This can lead to a non-anatomicalbone shape when the bone fully heals, which can also lead to prematurewear of articular cartilage in joint regions due to non-physiologicalalignments.

FIGS. 2-7 depict a femoral nail 10 according to an embodiment of thepresent disclosure. Femoral nail 10 configured for implantation in aleft leg and generally includes a proximal section 20, a distal section28 and an intermediate section therebetween. The intermediate sectionincludes a first curved portion 22, a straight portion 24, and a secondcurved portion 26.

In the particular embodiment depicted, proximal section 20 and distalsection 28 are each substantially straight along their respectivelengths. Distal section 28 terminates at a distal tip 14 which defines adistal end of nail 10. Proximal section 20 is generally cylindrical anddefines a longitudinal axis LA1 that extends along its length. Proximalsection 20 defines a proximal end 12 of nail 10 which is configured tobe coupled to an alignment/aiming instrument, such as by a threadedconnection. An example of an aiming instrument is disclosed in U.S. Pat.No. 6,039,739, the disclosure of which is incorporated herein byreference in its entirety. Also, as best shown in FIGS. 6 and 7,proximal end 12 includes a plurality of notches 16 a-c positioned atpredetermined intervals about the longitudinal axis LA1 of proximalsection 20. Such notches 16 a-c collectively form a clocking featurethat helps properly orient femoral nail 10 respective to a femur duringimplantation and may assist in the connection between thealignment/aiming instrument and femoral nail 10.

Femoral nail 10 also includes a plurality of screw holes 30, 32, 34, 40.42, 44 extending therethrough. As best shown in FIG. 3, nail 10 includesa first set of screw holes extending through proximal section 20 and theintermediate section, and a second set of screw holes extending throughdistal section 28. The first set of screw holes includes recon screwholes 30, a compression screw hole 32, and a static screw hole 34.Compression screw hole 32 is an elongate screw hole that defines an axisextending perpendicular to axis LA1 and allows for screw movement alongaxis LA1. Static screw hole 34 extends through intermediate section nearproximal section 20 and also defines a screw hole axis that isperpendicular to axis LA1. However, static screw hole 34 constrains anyscrew inserted therein from movement along axis LA1.

The recon screw holes 30 form three openings 30 a, 30 b, and 30 c at oneside (i.e., lateral side) of nail and two openings 30 b and 30 a,c at anopposite side (i.e., medial side) of nail. In this regard, openings 30 aand 30 c converge to single opening 30 a,c. Thus, a screw insertedthrough opening 30 a or 30 c extends through opening 30 a,c at theopposite side of nail 10, while a screw inserted through opening 30 b atone side of nail 10 extends through opening 30 b at the opposite side ofnail 10. As shown in FIG. 4, the screw holes 30 that are defined byopenings 30 a, 30 b, and 30 a,c define axes that extend at an obliqueangle relative to axis LA1 and lie in a plane extending in a direction Bas indicated by the arrow B in the figure. Such plane is referred toherein as a second plane or reconstruction plane (“Recon Plane”). Theaxes defined by openings 30 a, 30 b, and 30 a,c also extend toward afemoral head and femoral neck of a patient's femur when implantedtherein for a recon mode of fixation. Screw holes 30, 32, and 34 providefor multiple modes of fixation, such as the recon mode of fixation justmentioned as well as several others not specifically described herein.

The second set of screw holes, which extend through the distal sectionof nail, include static screw holes 40, a compression screw hole 42, anda transverse screw hole 44. Static screw holes 40 and compression screwhole 42 each extend through distal section 28 and define screw hole axesthat are perpendicular to a longitudinal axis of distal section 28 andlie within the Recon Plane, as best shown in FIG. 4. Transverse screwhole 44 extends through distal portion 28 transverse to screw holes 40a-b and 44 and has an axis that is perpendicular to the longitudinalaxis of distal section and lies within a plane which itself extends in adirection A, as shown in FIG. 3. Such plane is referred to herein as afirst plane or radius of center plane (“ROC Plane”), as is described inmore detail below. Also, transverse screw hole 44 is situated betweenstatic screw holes 40 along with compression screw hole 42.

In addition to the screw holes mentioned above, a bore 20 extendsthrough proximal end 12 of nail 10 along its length and through distaltip 14. Proximal section 20 is internally threaded along a portion ofthe length of bore 20 adjacent the proximal end 12. Such internalthreading is configured to mate with an alignment/aiming instrument andset-screw or cap, for example.

As mentioned above, the intermediate section includes a first curved orbent portion 22, a second curved or bent portion 26, and a straightportion 24. As depicted, first curved portion 22 extends distally fromproximal section 20, second curved portion 26 extends proximally fromdistal section 28, and straight portion 24 is positioned between firstand second curved portions 22, 26. Second curved portion 26 has a radiusof curvature R2 of about 500 to 1500 mm which has been determined toconform to the anterior femoral bow of 95% of the patient populationbased on a diversified population analysis using a central database thatcontains geometric data of human bones. Second curved portion 26 iscurved or bent in the first plane that extends in a direction A(indicated by arrow A in FIGS. 2 and 3). Hence, the first plane isreferred to as the ROC Plane as mentioned above. In the particularembodiment depicted, second curved portion 26 is curved/bent in only theROC Plane. However, it is contemplated that second curved portion 26 maybe curved/bent in other planes transverse to the ROC Plane as desired tomatch a patient(s) anatomy.

Straight portion 24 is positioned between first and second curvedportions 22, 26 and tapers from first curved portion 22 toward secondcurved portion 26 as this portion of nail 10 is intended to reside inthe transition region between the metaphysis and diaphysis of theproximal femur. Straight portion 24 also defines a longitudinal axis LA2extending along its length.

First curved portion 22 is shorter in length than second curved portion26 and has a first radius of curvature R1 of about 30 to 50 mm asdepicted in FIG. 5. In addition, first curved portion 22 is curved/bentin three separate, intersecting planes. More specifically, first curvedportion 22 is curved/bent in the first plane or ROC Plane, as shown inFIGS. 2 and 3. First curved portion 22 is also curved/bent in a secondplane or Recon plane that extends in a direction B, as depicted in FIG.4. Moreover, first curved portion 22 is curved/bent in a third planethat extends in a direction C, as best shown in FIG. 5. The bends/curvesin each of these planes define a radius of curvature of the first curvedportion 22. Radius of curvature R1, which is mentioned above, lies inthe third plane.

The bends of first curved portion 22 in each of the first, second, andthird planes has the effect of orienting longitudinal axis LA2 ofstraight portion 24 relative to longitudinal axis LA1 of proximalsection 20 at first, second, and third angles θ1, θ2, and θ3 withinthose respective planes. In other words, due to the multi-planarcurvature of first curved portion 22, axis LA2 is angled relative toaxis LA1 in the ROC Plane by a first bend angle θ1, in the Recon Planeby as second bend angle θ2, and in a Resultant Bend Plane by a thirdbend angle θ3, as shows in FIGS. 2, 4, and 5, respectively. Moreover, inthe embodiment depicted, bend angles θ1, θ2, and θ3 differ in magnitude.However, it is contemplated that bend angles θ1, θ2, and θ3 may be equalin each of the three planes. Where bend angles differ, third bend angleθ3 is a resultant of the first and second bend angles θ1 and θ2. In thisregard, the magnitude of θ3 and the orientation of the Resultant BendPlane relative to the other planes are a function of θ1 and θ2 and theangular orientation between the ROC Plane and Recon Plane in which suchfirst and second bends respectively lie. As an example, in the depictedembodiment, first bend angle θ1 is preferably 3 degrees in the ROCPlane, and second bend angle θ2 is preferably 4 degrees in the ReconPlane where the ROC Plane and Recon Planes are oriented at an obliqueangle α which is preferably 100 degrees, as best shown in FIG. 6. Thus,in this example, third bend angle is about 4.5 degrees and ResultantBend Plane is oriented about 59 degrees relative to ROC Plane and 41degrees relative to Recon Plane

It should be understood that while bend θ1, θ2, and θ3 are preferablyand respectively 3, 4, and 4.5 degrees and angle α is preferably 100degrees, these angles may differ. As such, angle α may be between 80 and120 degrees, first bend angle θ1 may be between 1.5 and 4.5 degrees,second bend angle θ2 may be between 3 and 6 degrees, and third bendangle θ3 may be between 3 and 8 degrees. Such angles have beendetermined to suitably fit 95% of the patient population without thefemoral cortex impingement described above based on a database analysisof a diverse population of bones.

FIG. 8 schematically illustrates the above described multi-planarbends/curves of first curved portion to help visualize the bends and howsuch bends are related to other structural features of nail 10, such asproximal notches 16 a-c. As shown, first curved portion 22 bends in theROC Plane at bend angle θ1 from axis LA2 of straight portion 24. Firstcurved portion 22 also bends in the Recon Plane from axis LA2 at bendangle θ2. This results in axis LA1 of proximal section 20 being angledrelative to axis LA2 of straight section by an angle θ3 in the ResultantBend Plane. Also, as can be seen, a Cartesian coordinate system isestablished such that the z-axis extends generally in ananterior-posterior direction, the x-axis extends generally in alateral-medial direction, and the y-axis extends generally in asuperior-inferior direction with the origin being located at theinterface between first curved portion 22 and straight portion 24. Theorigin may also be located anywhere from about 10% to 40% of the lengthof nail 10 measured from a proximal end thereof. The y-axis coincideswith longitudinal axis LA2 of straight section 24 and also defines theintersection between the ROC Plane, Recon Plane, and Resultant BendPlane. Thus, for the left legged nail 10 described herein, themulti-planar bend has the effect of orienting proximal section 20anteriorly and medially relative to straight portion 24. In this regard,proximal section 20 slopes posteriorly in the superior to inferiordirection which results in a canting away of nail 10 from an anteriorcortex of a femur at the common impingement area as illustrated inFIG. 1. It also aligns proximal section 20 and intermediate section withthe natural lateral-medial curve of a femur. It should be understoodthat these bends are mirrored for a right-legged femoral nail.

As also shown in FIG. 8, ROC Plane is oriented relative to the ReconPlane in the Cartesian coordinate system by the obtuse angle α. Thus,the Recon Plane is oriented relative to the x-plane within the Cartesiancoordinate system by α−90°. Thus, where angle α is 100 degrees, ReconPlane is angled relative to the x-plane by 10 degrees. This offset ofthe Recon Plane relative to the x-plane helps form the bend in theResultant Bend Plane and happens to also be equal to the angle ψ1. ψ1 isthe angle formed between the ROC Plane and a longitudinal axis LA3 whichbisects notches 16 a and 16 c, as shown in FIG. 7. In addition, an angleψ2 is formed between axis LA3 and Resultant Bend Plane. Thus, the anglebetween the ROC Plane and the Resultant Bend plane is equal to the sumof ψ1 and ψ2. Therefore, in the example provided above where α is 100degrees, ψ1 is 10 degrees, and ψ2 is 49 degrees, the angle between theROC Plane and Resultant Bend Plane is 59 degrees.

FIG. 9 illustrates the above described effect on femoral corteximpingement of the multi-planar bends. As shown, nail 10 overlays priorart nail 100 and, as a result of bends of first curve portion 22, nail10 cants away from the anterior cortex of the femur at the commonimpingement zone of prior art nail 100 thereby reducing the possibilityof femoral cortex impingement.

Femoral nail 10 may have alternative constructions to that describedabove while remaining within the scope of the invention. For example, inone embodiment, femoral nail 10 may not include a straight distal end28. Instead, second curved portion 24 may define the distal end 14 ofnail 10. In this regard, second curved portion 26 may curve about itscenter of curvature from straight portion 24 all the way to distal tip14 of femoral nail 10. Alternatively, distal section 28 may itself becurved/bent in one or more planes so that it has a different radius ofcurvature than that of second curved portion 26. In addition, proximalsection 20 may also be curved/bent along its length in one or moreplanes.

In another embodiment, nail 10 may not include a straight portion 24within the intermediate section. In such embodiment, second curvedportion 26 may then be positioned adjacent first curved portion 22 andmay extend distally therefrom. Thus, intermediate section may include afirst curved portion 22 with a first radius of curvature R1 that definesbends in three separate planes, and a second curved portion 26 extendingdistally from the first curved portion 22 and curved/bent about a centerof curvature in at least one plane. Although, in this embodiment, thestraight portion 24 may be absent, the advantages described above withregard to nail 10 may still be present.

Moreover, it should be understood that while it is described herein thatfirst curved portion 22 and second curved portion 26 are eachcurved/bent in the ROC Plane, this may not be the case in everyembodiment. It is possible that first curved portion 22 may be curvedbent in three separate planes where none of these planes are coincidentwith the plane in which second curved portion 26 is curved.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims.

The invention claimed is:
 1. A femoral nail comprising: a proximalportion configured to engage a driving tool for driving the femoral nailinto a femur; a distal portion remote from the proximal portion; and anintermediate portion disposed between the proximal portion and distalportion, the intermediate portion having a first bent section that isbent in three-dimensions such that a first bend of the first bentsection is in a first plane, a second bend is in a second plane, and athird bend is in a third plane, the first and second planes intersectingat an oblique angle relative to each other, the third bend defining anon-zero radius of curvature in the third plane of the first bentsection, the first plane being coplanar with an anterior-posteriorplane, the anterior-posterior plane being orthogonal to a medial-lateralplane, the medial-lateral plane extending between the second and thirdplanes.
 2. The femoral nail of claim 1, wherein the distal portion isstraight and includes a plurality of through-holes extending through thedistal end in a direction transverse to a distal end axis.
 3. Thefemoral nail of claim 1, wherein the first plane is greater than 80degrees and smaller than 120 degrees relative to the second plane. 4.The femoral nail of claim 3, wherein the first plane is 100 degreesrelative to the second plane.
 5. The femoral nail of claim 3, whereinthe first plane extends in an anterior-posterior direction, and thesecond plane extends substantially in a medial-lateral direction.
 6. Thefemoral nail of claim 1, wherein the first bend is 3 degrees relative toa longitudinal axis defined by an intersection between the first andsecond planes and the second bend is 4 degrees relative to thelongitudinal axis.
 7. The femoral nail of claim 6, wherein the thirdbend is greater than 4 degrees relative to the longitudinal axis.
 8. Thefemoral nail of claim 1, wherein the proximal portion of the femoralnail includes a plurality of through-holes extending therethrough, atleast a first and second through-hole of the plurality of through-holeshaving respective first and second through-hole axes that lay in thesecond plane.
 9. The femoral nail of claim 1, wherein the proximalportion includes at least one rotational alignment characteristic forindicating a rotational alignment of the femoral nail relative to afemur, the rotational alignment characteristic being rotationally offsetfrom the third plane by an acute angle.
 10. The femoral nail of claim 9,wherein the acute angle is less than 50 degrees.
 11. The femoral nail ofclaim 10, wherein the rotational alignment characteristic is anengagement notch configured to engage the driving tool.
 12. The femoralnail of claim 1, wherein the third plane intersects the second plane atan acute angle less than 50 degrees.
 13. The femoral nail of claim 1,wherein curvatures of each of the bends begin their respectivecurvatures at a common origin.
 14. The femoral nail of claim 1, whereinthe intermediate portion includes a second bent section disposed betweenthe distal portion and first bent section.
 15. The femoral nail of claim14, wherein the intermediate portion includes a straight sectiondisposed between the first and second bent sections.
 16. The femoralnail of claim 14, wherein the second bent section has a non-zero radiusof curvature in the first plane.
 17. The femoral nail of claim 1,wherein distal portion defines a distal tip of the femoral nail, and thefirst bent section bends in an anterior direction away from the distaltip.
 18. A femoral nail comprising: a proximal section having alongitudinal axis extending along its length; a distal section remotefrom the proximal section; and an intermediate section disposed betweenthe proximal section and distal section and having a straight portionand first bent portion, the first bent portion being disposed betweenthe straight portion and the proximal section, the first bent portionbeing bent in first, second, and third planes such that a longitudinalaxis of the straight portion is oriented relative to a longitudinal axisof the proximal section by first, second, and third angles within therespective first, second, and third planes, and wherein the first,second, and third angles differ from one another, wherein theintermediate section further includes a second bent portion disposedbetween the straight portion and distal section, the second bent portionbeing bent in the first plane.
 19. A femoral nail comprising: a firstsection having a first screw hole extending through a sidewall thereofand defining a screw hole axis configured to extend toward a femoralhead when the femoral nail is implanted within a femur, the screw holeaxis lying in a first plane; and a second section extending from thefirst section and having first and second curved portions, the firstcurved portion being positioned closer to the first section than thesecond curved portion, the first curved portion being curved in thefirst plane and in second and third planes that are each different fromthe first plane, the second curved portion having a proximal-distallength greater than that of the first curved portion, and the secondcurved portion being curved in the second plane.
 20. The femoral nail ofclaim 19, wherein the first and second plane are oriented relative toeach other at an obtuse angle, and the third plane is disposed betweenthe first and second planes and is oriented relative to the second planeat an acute angle.